1. Field
Embodiments relate to an apparatus and method for charging a battery pack. More particularly, embodiments relate to an apparatus and method for charging a battery pack that may be used while being charged, regardless of the number of cells of the battery pack.
2. Description of the Related Art
In general, a secondary battery, as opposed to a primary battery, refers to a battery that may be charged as well as discharged. Secondary batteries are used for portable electronic devices, e.g., a mobile phone, a notebook computer, camcorder, and so forth. Secondary batteries include a nickel-cadmium secondary battery, a nickel-hydrogen secondary battery, and a lithium ion secondary battery. Lithium ion secondary batteries have a higher driving voltage and a higher energy density per unit weight than nickel-cadmium and nickel-hydrogen secondary batteries. Thus, lithium ion secondary batteries are currently more widely used than other types of secondary batteries.
Secondary batteries are used for a battery pack of a mobile telephone, a personal digital assistant (PDA), an MP3 player, a notebook, an electrical bicycle, and so forth. For example, current mobile telephones, PDAs, and MP3 players may have a single cell battery pack that uses one secondary battery or 2 to 4 cell battery packs in which two to four secondary batteries are serially coupled. In addition, electrical bicycles currently use 7 to 13 cell battery packs in which 7 to 13 secondary batteries are serially coupled. Different chargers are used in accordance with the number of cells in the battery pack and these different charges are not interchangeable for the different battery packs.